Designates the staunchion wall thickness. This is an optional entry, used only if there is a staunchion or dummy leg attached to the bend.
Typical units (depending on your unit system):
-
in
-
mm
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cm
The stress intensification factors for dummy legs are from the paper: "Stress Indices for Piping Elbows with Trunnion attachments for Moment and Axial Loads.", PVP Vol. 129, 1987.
The equation (1.7)i = (C2)(K2) is used to get from the calculated (C2) coefficients to the stress intensification factor (i). If you do not define a value for the stress concentration factor, it defaults to 2.0.